The Australia Telescope National Facility Pulsar Catalog [1]} lists over 2300 radio pulsars.
Several radio studies [2]}, [3]}, [4]} have measured the polarization for many of these pulsars.
Radio pulsars typically show moderate-to-strong linear polarization (\(p_{L}\) ), being stronger
for those of higher spin-down energy-loss rate [4]}.
The linear polarization sometimes exhibits a characteristic swing or sweep of the position angle in an S-like shape near the pulse center, which is routinely interpreted in terms of the rotating vector model [6]}.
For this model the point of emission is assumed to be in the polar cap region of the pulsar where a dipolar magnetic-field line points with a small angle (beamwidth) towards the observer.
The two free parameters of this simple model are the angle between the axes of rotation and the orientation of the magnetic dipole, and the view angle between the line of sight and the rotation axis.
The variation of the radio position angle from some pulsars [7]} can be described by this model.
